// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <iostream>

#include "base/hash.h"
#include "base/logging.h"
#include "device/bluetooth/bluetooth_uuid.h"

int main(int argc, char** argv)
{
    if (argc <= 2) {
        std::cout << "Generates hash values given UUIDs using the same method\n"
                  << "as in bluetooth_metrics.cc.\n"
                  << "\n"
                  << "Output is formatted for including into histograms.xml.\n"
                  << "Note that tools/metrics/histograms/pretty_print.py will\n"
                  << "sort enum entries for you.\n"
                  << "\n"
                  << "Usage: " << argv[0] << " <uuid> <label> [uuid2 label2...]\n"
                  << "       The UUIDs may be short UUIDs, and will be made\n"
                  << "       canonical before being hashed.\n"
                  << "\n"
                  << "Example: " << argv[0] << " FEFF foo FEFE bar\n"
                  << "  <int value=\"62669585\" "
                     "label=\"foo; 0000feff-0000-1000-8000-00805f9b34fb\"/>\n"
                  << "  <int value=\"643543662\" "
                     "label=\"bar; 0000fefe-0000-1000-8000-00805f9b34fb\"/>\n";
        return 1;
    }

    for (int i = 1; i < argc; i = i + 2) {
        std::string uuid_string(argv[i]);
        std::string label_string((i + 1 < argc) ? argv[i + 1] : "");
        device::BluetoothUUID uuid(uuid_string);
        std::string uuid_canonical_string = uuid.canonical_value();
        uint32_t hash = base::SuperFastHash(uuid_canonical_string.data(),
            uuid_canonical_string.size());

        // Strip off the sign bit because UMA doesn't support negative values,
        // but takes a signed int as input.
        hash &= 0x7fffffff;

        std::cout << "  <int value=\"" << hash << "\" label=\"" << label_string
                  << "; " << uuid_canonical_string << "\"/>\n";
    }
    return 0;
}
